Titanium-base alloys



TITAN lUM-BASE ALLOYS Walter L. Finlay and Howard T. Clark, .ha, Beaver, Pa., and John A. Snyder, Wilmington, Del, assiguors, by mesne assignments, to Rem-Cm Titanium, Ina, Midland, Pa, a corporation of Pennsylvania No Drawing. Application January 29, 1952, Serial No. 268,934

6 Claims. (Cl. 75-1755) This invention relates to titanium-base alloys and contemplates a group of ternary alloys of titanium With molybdenum and manganese.

In application Serial Number 134,774, filed December 23, 1949, now abandoned, the present inventors have disclosed numerous alloys in which the beta or high temperature phase of titanium has been stabilized at room temperature by the addition of not less than about 12 atomic percent of one or more beta stabilizing ingredients. The most effective beta stabilizers are manganese, molybdenum, chrominum, and iron. The general physical properties of the beta alloys are improved by the use of two or more of the beta stabilizing ingredients, an example being the quaternary alloys of titanium with manganese, molybdenum, and chromium claimed in said application Serial Number 134,774.

The present invention comprises the further discovery that in the ternary titanium-manganese-molybdenum system there exists in addition to alloys in the beta phase, alloys of excellent properties and of mixed alpha-beta structure, the content of the beta stabilizer ingredient being inadequate to completely stabilize the beta phase. Representative alloys of this system and their properties, as vacuum annealed at 700 C., are as follows:

The titanium used in the manufacture of such alloys States Paten may be either substantially pure titanium, as made by the iodide process, or may be commercial titanium with its usual content of such contaminants as carbon, oxygen, and nitrogen. In the foregoing table, alloys 1, 2, 3, and 5 were made from commercial titanium, while the others were made from iodide titanium. All of these alloys show excellent bend ductility. Alloys 4, 5, and 7, for example, may be bent to an included angle of not over on a zero radius. Moreover, the alloys are stable under high temperature conditions, no material loss of elongation or bend ductility being sustained by exposure to a temperature of 300 C. for 64 hours.

To the extent of their common subject matter, the present application is a continuation-in-part of the aforementioned application Serial Number 134,774, filed December 23, 1949.

What is claimed is:

1. An alloy containing about: 1 to 15% manganese, 1 to 21% molybdenum, and the balance substantially titanium characterized in having an ultimate strength at least 10% in excess of the unalloyed titanium base metal and in having a high degree of ductility.

2. An alloy consisting of about: 1 to 15% manganese, 1 to 21% molybdenum and the balance titanium.

3. An alloy containing about: 1 to 15% manganese, 1 to 21% molybdenum, and the balance substantially titanium, characterized in having a mixed alpha-beta microstructure, an ultimate strength at least 10% in excess of the unalloyed titanium base metal, and a high degree of ductility.

4. An alloy containing about: 1 to 15% manganese, 1 to 21% molybdenum, and the balance substantially titanium, characterized in having an ultimate strength of at least 115,000 p. s. i. and a tensile elongation of at least 7%.

5. An alloy consisting of 1-15% manganese, 116% molybdenum and the balance titanium.

6. An alloy consisting essentially of about: 1-15% manganese, 1-16% molybdenum and the balance titanium, characterized in being ductile and in having a tensile strength of at least 115,000 p. s. i.

References Cited in the file of this patent Titanium: Report of Symposium, Dec. 16, 1948, sponsored by Oflice of Naval Research, Washington, D. 0., pages 15, 16, 111, 112, 123 and 140.

Research and Development on Titanium Alloys (Part 2) pub. as AF Technical Report No. 6218, Part 2; June 1950 work by Battelle Memorial Institute, pages 46, 47 and 87 relied on.

Summary ReportDevelopment of Titanium-Base Alloys, AF Technical Report No. 6623, June 1951, pub. by Battelle Memorial Institute, Columbus, Ohio, pages 53 and 54. 

1. AN ALLOY CONTAINING ABOUT: 1 TO 15% MANGANESE, 1 TO 21% MOLYBDENUM, AND THE BALANCE SUBSTANTIALLY TITANIUM CHARACTERIZED IN HAVING AN ULTIMATE STRENGTH AT LEAST 10% IN EXCESS OF THE UNALLOYED TITANIUM BASE METAL AND IN HAVING A HIGH DEGREE OF DUCTILITY. 